Furnace-damper device



May 31,1927.

J. VRBA FURNACE DAMPER DEVICE Filed Nov. 24; 1924 li atented May 31, 1927.

uurrso STATES PATENT OFFICE.

JAMES vnnii, or MAnsnALL'roWN, Iowa, sssrenon TO nnnnox runnaon ooMPnNY,

i MARSHALIJTOWN, IOWA.

FURNACE-DAMPER DEVICE.

Application filed November24, 1924. Serial No. 751,959.

in the construction of modern furnaces, there is ordinarily a combustion chamber, a radiating drum between the combustion chamber and the line, and a furnace casing 5 surrounding both the COll'llltiSlllOll chamber and the radiating drum l'rom which the hot air pipes are extended. In furnaces ot this class it is customary to provide a damper device by which the products of COl-llbHStiOH 1o may be permitted to pass directly "from the coii'ibuetion chamber to the hue when the damper is opened, or such products may be compelled to circulate through the radiating drum before 13* sing to the flue when the damper is in its closed position. These dampers are at times subjected to intense heat and after being installed are not conveniently accessible, and if any leakage should occur around the damper stem, burned products of combustion would pass into the turnace casing and from there be circulated through the building being heated, with obvious undesirable results. i

My object is to provide a damper device of simple, durable and inexpensive construetion formed complete of simple castings and without machine work, and which may be .rez'idily, quickly and easily installed, and not readily impaired or burned out by excessive heat; and i Further my object is to provide a device ct this kind in which the escape of products or" combustion around the damper stem is prevented. i

My invention consists in the construction, arrangement and combination of the various parts of the device, whereby the objects contemplated are attained, as l'iereina'l ter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawings in which:

Figure 1 shows a perspective view of a portion of a furnace with my improved damper device installed therein.

Figure 2 shows an enlarged detail view of a portion of the deflector plat-e of a radiating :lruni with my improved damper device installed therein with the damper in open position.

Figure 3 shows a similar view with the damper in a closed position. i

liigure t shows a vertical sectional View on the line il of Figure 3.

Figure 5 shows a top elevation of my improved thunper device with the damper con- I have used the reference numeral l0 to indicute generally the furnace combustion chamber and 11. the radiating drum. E'hirroundmg the combustion chamber and the drum is the usual furnace casing 12. From the ra iating drum, the flue pipe 13 is extended. The top of the radiating drum'is substantially lint and is indicated generally by the numeral Ll. Within the radiating drum there is usually provided a cast metal deflector plate 15 having an opei'iing therein. The deflector plate is customarily arranged with in the drum litbetween the inlet pipe and the discl'i-arge pipe that communicates with the drum, and the opening is so arranged that when it is unobstructed there is sub stanti ally a straight passageway through the drum, but when the opening is closedthe deflector plate causes the products of combus tion passing through the drum to be widely distributed tl'iroughout the drum to increase radiation. The shape and positions ot said deflector plate vary to a considerable extent. It is, however, in common use and it is believed to be unnecessary to more fully and particularly illustrate or describe it.

In the construction of the deflector plate I provide at the bottom of the hue opening therein an enlargedtapered socket device 16 having a substantially flat horizontal top, and in the center of the top having a tapered depression, as shown in Figure l. At the top of the flue opening there is formed in the deflector plate an enlarged cylindrical body 17 having a vertical opening through it, and also having a downwardly extended shoulder 18 at one side. At the margin of the damper opening there is formed a flange 19, as shown in Figure 7, for purposes hereinafter made clear. V

The damper proper comprises a body portion 20 having at its lower end a tapering bearing 20 to receive a pivot pin 20",:1nd having at its top socket shaped to receive an angular damper pin 29, hereinafter de scribed, and formed 7 on i one side of the damper near its upper end is a stop'de'vice 20 designed to engage theshoulder 18 and limit the opening movement of the damper. Mounted on top of the radiating drum is a valve, operating and sealing device comprising a lower circular plate 21 formed with a central opening and also with a raised tapered rib 22 surrounding thecentral opening, and a circular depression surroundiinz the rib 22, and with flatsurface extended horizontally outwardly to the exterior of the circular plate 21, as shown in Figure 4. On the under surface of the plate 21 there is a downwardly extended circular flange 23 slightly spaced apart from the central opening, and a downwardly extended flange 2% at the outer edge. Between said flanges 23 and 24: there is formed a dead air chamber 25, This lower plate 2L is permanently connected with the part 14; by bolts 26, and preferably a packing" of asbestus, or the like, 27, is provided between the flanges 23 and 2a and the part lat.

Mounted on top of the plate 21 is a second circular plate 28 formed with, a central opening in which there fixedly mounted an angular shaft 29. designed to extend downwardly through the plate 28 through an opening iuthe plate 21 and the partla, and through the body portion ll into an angular recess provided forit in the top of the damper, as shown in Figure 4. This angular recess has an opening at one side of 'itslower end. to permit any line ashes or dust, to pass through to thereby avoid such accumulation thereof as would tend to raise the shaft 29. The lower end of the shaft 28. is shown projected through this opening in Figure 4. i t Formed in the under surface of the plate 28. is an annular groove, tapered and do signed to fit the rib 22, and surrounding said groove is an annular rib 3O tapered and shaped to fit into the corresponding roove in the upper surface of the plate 21, and at the outer edge of the plate 28 there is a downwardly extended rib 31 to engage the top surface of the plate 21, and between the ribs 80 and 31 there is a dead air space 32 in which the heads of the bolts 26 are received. Extended outwardly from the plate 28 is an arm 33 connected to arod 3i and extended through the furnace casing front, so that the damper may be adjusted from the front of the furnace.

In practical use the parts are; assembled as follows: The plate 21 is bolted to the top of the radiating drum, then the damper is placed in positionin the damper opening with the taperedbearing 20 in the tapered socket 16, then the plate 28 is applied and the shaft 29 extended downwardly until it enters the upper end of the damper, and when in this position the plate'28 will have its taperedrib 30 and its rib 31 bothheld in frictional engagement with the corresponding parts of the plate 21. by gravity. The rod 34 is then connected to the arm 33, and the device is ready for use.

In use, it is not practical to provide a gas tight joint at the lower of the damper shaft 29, because of the extreme changes in temperatures to which these parts are Stilljected. Hence, products of cmnbustion will pass upwardly through the radiating drum surrounding the shaft 29. I am aware that heretofore thcro has been provided a stationary plate surrounding the upper end of the damper shaft and provided with a tapered annular rib, and on top of it there has been provided a srond ilate capable of rotation and containing the ilaniper shaft and. having an annular tapered groove to receive the annular rib of the lower stationary plate. However, it has been proven im 'iracticalile in use to make these tapered joints tight enough under all conditions to maintain gas tight joints.

My improreinent, however, comprises the extending of the upper and lower plates outwardly to a considerable distance and then forniing a downwardly extended rib in the outer surface ol the upper plate to engage the top surface of the lower plate and to form a dead air space surrounding the bolt heads therein, 1 have dcInonstrated in practice that by this improved construetion and with the use of ordinary castings not machined, I have been able to provide a gas tight joint, for the reason that the said dead airspace for the outer flange 3]. acts in such a manner as to tend to equalize the pressures on the interior and exterior of the plates 21 and 28 to such an extent as to prevent the escape of gas from the radiatmg drum of the lnterior of the furnace cass- Furthermore, by providing the downwardly extended fiange2l on the lower plate 21, and also providing a dead air space between the said flange 2st and the flange 23, I prevent the escape of gas through thebolt openings.

Another advantage gained by the use of my improveddamper device is thatthe shaft 29 is protected from the intense application of heat by having its upper portion completely surrounded by the enlarged body 17,

and its lower portion received into an enlarged socketdevice 20 and terminating at apoint above the thin body portion of the damper. The lower end of the damper formed with a cast tapered hearing which provides a hearing at the bottom of the damper. Heretofore it has been customary to connect and support a damper by means of a shaft extended through it and exposed at various points to the action of the heat,

and this has resulted in frequent burning out of the exposed portions of said shaft.

With my improvement the entire device the lit;

may be made of simple castings which do not need to be machined after casting, and which can be readily, quickly and easily assembled, and which are extremely durable and will prevent the escape of gas into the furnace casing.

I claim as my invention:

1. In a damper control device, the combination of two circular plates, the lower one formed with a central opening and with a raised rib surrounding the opening, an annular groove surrounding the raised rib, an outwardly extended portion beyond said annular groove, and an upper circular plate having an annular groove to receive said annular rib on the lower plate, an annular rib to enter said annular groove in the lower plate, and an outwardly extended portion terminating in a downwardly extended flange to engage the top surface of the outer portion of the lower plate and to form between the two plates a dead air chamber.

2. In a damper control device, the combination of two circular plates, the lower one formed with a central opening and with raised rib surrounding the opening, an annular groove surrounding the raised rib, an outwardly extended portion beyond said annular groove, and an upper circular plate having an annular groove to receive said annular rib on the lower plate, an annular rib to enter said annular groove in the lower plate, and an outwardly extended portion terminating in a downwardly extended flange to engage the top surface of the outer portion of the lower plate and to form be opening at its upper end, for

tween the two plates a dead air chamber, said lower plate being also formed with two downwardly extended annular flanges spaced apart from each other, and with bolt openings extended through it between said downwardly extended flanges to form a dead air chamber surrounding said bolt openings.

3. The combination with a radiator drum of a deflector plate formed with a damper opening and having at the bottom of the damper opening an enlarged socket, and also having at the top of the damper opening an enlarged body portion formed with a socket, and a damper body having formed at its lower end a tapered bearing fitted into said socket and having formed at its upper end an enlarged body formed with a pivot pin the purposes stated.

l. The combination with a radiator drum of a deflector plate formed with a damper opening and'having at the bottom of the damper opening an enlarged socket, and also having at the top 01 the damper opening an enlarged body portion formed with a socket, and a damper body having formed at its lower end a tapered bearing fitted into said socket and having formed at its upper end an enlarged body formed with a pivot pin opening at its upper end, said damper being also provided with a stop device formed at one side, and the enlarged body portion therein and being formed with a shoulder for engaging the stop device and limiting the rotary movement of the damper.

JAMES VRBA. 

